A conventional communication system typically involves transmitting a communications signal representing one or more information signals from a conventional communications transmitter to a conventional communications receiver over a communication channel. A noise figure (NF) is a measure of degradation of a signal to noise ratio (SNR) of the communications signal, caused by components of the conventional communications receiver. Commonly, the conventional communications receiver includes a series of amplifiers to optimize a total NF of the conventional communications receiver.
The communication channel contains a propagation medium that the communications signal passes through before reception by the conventional communications receiver. The propagation medium of the communications channel may introduce interference and/or distortion into the communications signal causing the communications signal as received by the conventional communications receiver to differ from the communications signal as transmitted by the conventional communications transmitter. For example, the propagation medium of the communications channel may cause one or more asymmetries in the communications signal. The one or more asymmetries may cause one or more offsets in the communications signal.
To correct for the one or more asymmetries in the communications signal, the conventional communications receiver adjusts the communications signal by a single offset adjustment correction. The conventional communications receiver usually combines the single offset adjustment correction with the communications signal before a first amplifier from the series of amplifiers. In this situation, the single offset adjustment correction may provide a large amount of compensation. The large amount of compensation allows the single offset adjustment correction to compensate for larger offsets in the communications signal. However, the large amount of compensation does not allow the single offset adjustment correction to compensate for smaller offsets in the communications signal. Alternatively, the conventional communications receiver may combine the single offset adjustment correction with the communications signal after a last amplifier from the series of amplifiers. In this situation, the single offset adjustment correction may provide a small correction. The small correction allows the single offset adjustment correction to may compensate for smaller offsets in the communications signal. However, the small resolution does not allow the single offset adjustment correction to compensate for larger offsets in the communications signal.
Thus, what is needed is an apparatus and method compensate for one or more offsets in the presence of one or more asymmetries that overcomes the shortcomings described above.
The present invention will now be described with reference to the accompanying drawings. In the drawings, like reference numbers generally indicate identical, functionally similar, and/or structurally similar elements. The drawing in which an element first appears is indicated by the leftmost digit(s) in the reference number.